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Susceptibilities and Taylor coefficients of magnetic QCD from perturbation theory

Eduardo S. Fraga1,*, Letícia F. Palhares2,†, and Tulio E. Restrepo3,‡

  • *Contact author: fraga@if.ufrj.br
  • †Contact author: leticia.palhares@uerj.br
  • ‡Contact author: trestre2@central.uh.edu
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Phys. Rev. D 113, 014014 – Published 13 January, 2026

DOI: https://doi.org/10.1103/ql4q-w57l

Abstract

We compute the coefficients c2(T,B) and c4(T,B) of the Taylor expansion for the pressure in powers of μB/T in the presence of a large magnetic field within perturbative quantum chromodynamics (QCD) at finite temperature and baryon density up to two-loops for Nf=3 flavors with physical quark masses. We also present results for the excess of pressure, baryon density, and baryon number susceptibility as functions of μB, as well as susceptibilities as functions of the temperature in the {μB,μQ,μS} basis. Our results can be directly compared to recent lattice QCD data. Even though current lattice results do not overlap with its region of validity, perturbative results seem to be compatible with those obtained on the lattice for large temperatures.

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Phys. Rev. D 113, 014014– Published 13 January, 2026
  • Received 29 July 2025
  • Accepted 24 December 2025
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